(1) Field of the Invention
The present invention relates to tissue manipulators for use in vitreous surgery, in particular, a tissue manipulator that combines a fiber optic endoilluminator with a coaxial bipolar diathermy and an infusion/aspiration system.
(2) Description of the Related Art
Vitreous surgery tissue manipulators of the type provided by the present invention commonly comprise a handheld piece having a hollow needle extending from one end. A plurality of parallel fiber optic members extend through the hand piece and the hollow needle, and terminate at distal ends adjacent the distal end of the needle. The proximal end of the tissue manipulator hand piece is connected to a light conducting member that conveys light from an external light source to the manipulator. The light conducting member illuminates the proximal ends of the fiber optic members extending through the tissue manipulator, causing a beam of light to be directed outwardly from the distal ends of the fiber optic members adjacent the distal end of the needle.
Because the tissue manipulator needle is used by penetrating the needle into the vitreous humor of an eye, the external dimensions of the needle must be kept as small as possible. This, in turn, limits the cross-sectional diameter of the bore through the needle and the number of fiber optic members extending through the needle bore.
Each of the fiber optic members extending through the manipulator hand piece and needle is surrounded by a non-light conducting cladding. The cladding directs the light illuminating the proximal ends of the fiber optic members through the members and out their distal ends. A disadvantage of this type of conventional tissue manipulator is that much of the cross-sectional area of the fiber optic members extending through the needle bore is taken up by the cladding surrounding each of the members and the gap between adjacent members, reducing the actual amount of cross-sectional area of the needle bore that is taken up by the light conveying optic fibers.
Many conventional tissue manipulators are provided with a membrane pic extending from the distal end of the manipulator needle. The pic is used for engaging tissues in the vitreous humor of an eye and for retinal membrane stripping. The pics are commonly formed by grinding down the distal ends of the manipulator needle until only a narrow portion of the needle side wall remains. This narrow portion of side wall is then given a general triangular shape, with a section of the narrow side wall adjacent the apex of the triangle being bent over at a 45.degree. angle into the projected path of light from the distal end of the fiber optic members extending through the needle.
Because the side walls of the needles are made very thin to devote as much of the cross-sectional area available to the fiber optic members, a membrane pic formed in the above-described manner from the thin side walls of the needle will tend to bend or break over a period of use. Additionally, because the membrane pic is bent at a 45.degree. angle into the projected path of light from the distal end of the needle, the light beam will often reflect off of the interior surface of the pic and the membrane pic itself will often cast a shadow on the retinal surface adjacent the pic, making it difficult for the pic user to observe the end of the pic and the retinal surface adjacent the pic.
Often, in performing vitreous surgery, a separate infusion or aspiration needle is needed to supply infusion fluid or suction, respectively. When infusion or aspiration is required in vitreous surgery, a third hand for operating the infusion or aspiration system is also often required.
Moreover, in performing vitreous surgery, it is often necessary to coagulate bleeding vessels either on a retinal surface or beneath pre-retinal membranes. This situation requires the use of a separate manual bipolar diathermy instrument to stop the bleeding. When use of the diathermy instrument is necessary, an additional hand is often required to manipulate the instrument.
It is an object of the present invention to overcome the disadvantages associated with prior art tissue manipulators by providing a surgical instrument for use in vitreous surgery that combines a more efficient fiber optic endoilluminator membrane pic with a coaxial bipolar diathermy or an infusion/aspiration system in a single instrument.
It is a further object of the present invention to provide a fiber optic endoilluminator with an increased illumination capability over the prior art illuminators having the same cross-sectional area.
It is a further object of the present invention to provide a fiber optic light conveying member that projects an increased amount of illumination from its distal end than prior art fiber optic members having the same cross-sectional diameter at their distal ends due to an improved light gathering configuration of the proximal end of the fiber optic member that is subjected to a source of illumination.
It is also an object of the present invention to provide a tissue manipulator pic that is stronger than prior art membrane pics and does not reflect the beam of light projected from the endoilluminator or cast shadows on the retinal surface.
It is a still further object of the present invention to provide a connector at the proximal end of the light conveying fiber optic member that absorbs heat radiated by the source of illumination and conveys the heat away from the proximal end of the fiber optic member.